Compute {{MATH_67}} {{CMD_68}} Set {{MATH_69}} and {{MATH_70}}. Since both {{MATH_71}} and {{MATH_72}} are differentiable functions at {{MATH_73}}, and {{MATH_74}} this situation is ripe for L'H{{CMD_75}}pital's Rule. Now {{MATH_76}} and {{MATH_77}} L'H{{CMD_78}}pital's rule tells us that {{MATH_79}} {{CMD_80}} {{CMD_81}}